 |
| Titel |
Late Glacial and Holocene changes in vegetation cover and climate in southern Siberia derived from a 15 kyr long pollen record from Lake Kotokel |
| VerfasserIn |
P. E. Tarasov, E. V. Bezrukova, S. K. Krivonogov |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1814-9324
|
| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 5, no. 3 ; Nr. 5, no. 3 (2009-07-01), S.285-295 |
| Datensatznummer |
250002534
|
| Publikation (Nr.) |
 copernicus.org/cp-5-285-2009.pdf |
|
|
|
|
|
| Zusammenfassung |
| In this study a radiocarbon-dated pollen record from Lake Kotokel (52°47´ N, 108°07´ E, 458 m a.s.l.) located in southern Siberia east of Lake
Baikal was used to derive quantitative characteristics of regional
vegetation and climate from about 15 kyr BP (1 kyr=1000 cal. yr) until
today. Quantitative reconstruction of the late glacial vegetation and
climate dynamics suggests that open steppe and tundra communities
predominated in the study area prior to ca. 13.5 kyr BP and again during the
Younger Dryas interval, between 12.8 and 11.6 kyr BP. The pollen-based
climate reconstruction suggests lower-than-present mean January (~−38°C) and July (~12°C)
temperatures and annual precipitation
(~270–300 mm) values during these time intervals. Boreal woodland
replaced the primarily open landscape around Kotokel three times at about
14.8–14.7 kyr BP, during the Allerød Interstadial between 13.3–12.8 kyr BP
and with the onset of the Holocene interglacial between 11.5 and 10.5 kyr BP, presumably
in response to a noticeable increase in precipitation, and in
July and January temperatures. The maximal spread of the boreal forest
(taiga) communities in the region is associated with a warmer and
wetter-than-present climate (Tw~17–18°C, Tc~−19°C, Pann~500–550 mm)
that occurred ca. 10.8–7.3 kyr BP.
During this time interval woody vegetation covered more than 50% of the
area within a 21×21 km window around the lake. The pollen-based best
modern analogue reconstruction suggests a decrease in woody cover
percentages and in all climatic variables about 7–6.5 kyr BP. Our results
demonstrate a gradual decrease in precipitation and mean January temperature
towards their present-day values in the region around Lake Kotokel since
that time. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|